xref: /openbmc/linux/arch/sh/kernel/machine_kexec.c (revision 3213486f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * machine_kexec.c - handle transition of Linux booting another kernel
4  * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
5  *
6  * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
7  * LANDISK/sh4 supported by kogiidena
8  */
9 #include <linux/mm.h>
10 #include <linux/kexec.h>
11 #include <linux/delay.h>
12 #include <linux/reboot.h>
13 #include <linux/numa.h>
14 #include <linux/ftrace.h>
15 #include <linux/suspend.h>
16 #include <linux/memblock.h>
17 #include <asm/pgtable.h>
18 #include <asm/pgalloc.h>
19 #include <asm/mmu_context.h>
20 #include <asm/io.h>
21 #include <asm/cacheflush.h>
22 #include <asm/sh_bios.h>
23 #include <asm/reboot.h>
24 
25 typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
26 				      unsigned long reboot_code_buffer,
27 				      unsigned long start_address);
28 
29 extern const unsigned char relocate_new_kernel[];
30 extern const unsigned int relocate_new_kernel_size;
31 extern void *vbr_base;
32 
33 void native_machine_crash_shutdown(struct pt_regs *regs)
34 {
35 	/* Nothing to do for UP, but definitely broken for SMP.. */
36 }
37 
38 /*
39  * Do what every setup is needed on image and the
40  * reboot code buffer to allow us to avoid allocations
41  * later.
42  */
43 int machine_kexec_prepare(struct kimage *image)
44 {
45 	return 0;
46 }
47 
48 void machine_kexec_cleanup(struct kimage *image)
49 {
50 }
51 
52 static void kexec_info(struct kimage *image)
53 {
54         int i;
55 	printk("kexec information\n");
56 	for (i = 0; i < image->nr_segments; i++) {
57 	        printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
58 		       i,
59 		       (unsigned int)image->segment[i].mem,
60 		       (unsigned int)image->segment[i].mem +
61 				     image->segment[i].memsz,
62 		       (unsigned int)image->segment[i].memsz);
63 	}
64 	printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
65 }
66 
67 /*
68  * Do not allocate memory (or fail in any way) in machine_kexec().
69  * We are past the point of no return, committed to rebooting now.
70  */
71 void machine_kexec(struct kimage *image)
72 {
73 	unsigned long page_list;
74 	unsigned long reboot_code_buffer;
75 	relocate_new_kernel_t rnk;
76 	unsigned long entry;
77 	unsigned long *ptr;
78 	int save_ftrace_enabled;
79 
80 	/*
81 	 * Nicked from the mips version of machine_kexec():
82 	 * The generic kexec code builds a page list with physical
83 	 * addresses. Use phys_to_virt() to convert them to virtual.
84 	 */
85 	for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
86 	     ptr = (entry & IND_INDIRECTION) ?
87 	       phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
88 		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
89 		    *ptr & IND_DESTINATION)
90 			*ptr = (unsigned long) phys_to_virt(*ptr);
91 	}
92 
93 #ifdef CONFIG_KEXEC_JUMP
94 	if (image->preserve_context)
95 		save_processor_state();
96 #endif
97 
98 	save_ftrace_enabled = __ftrace_enabled_save();
99 
100 	/* Interrupts aren't acceptable while we reboot */
101 	local_irq_disable();
102 
103 	page_list = image->head;
104 
105 	/* we need both effective and real address here */
106 	reboot_code_buffer =
107 			(unsigned long)page_address(image->control_code_page);
108 
109 	/* copy our kernel relocation code to the control code page */
110 	memcpy((void *)reboot_code_buffer, relocate_new_kernel,
111 						relocate_new_kernel_size);
112 
113 	kexec_info(image);
114 	flush_cache_all();
115 
116 	sh_bios_vbr_reload();
117 
118 	/* now call it */
119 	rnk = (relocate_new_kernel_t) reboot_code_buffer;
120 	(*rnk)(page_list, reboot_code_buffer,
121 	       (unsigned long)phys_to_virt(image->start));
122 
123 #ifdef CONFIG_KEXEC_JUMP
124 	asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
125 
126 	if (image->preserve_context)
127 		restore_processor_state();
128 
129 	/* Convert page list back to physical addresses, what a mess. */
130 	for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
131 	     ptr = (*ptr & IND_INDIRECTION) ?
132 	       phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {
133 		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
134 		    *ptr & IND_DESTINATION)
135 			*ptr = virt_to_phys(*ptr);
136 	}
137 #endif
138 
139 	__ftrace_enabled_restore(save_ftrace_enabled);
140 }
141 
142 void arch_crash_save_vmcoreinfo(void)
143 {
144 #ifdef CONFIG_NUMA
145 	VMCOREINFO_SYMBOL(node_data);
146 	VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
147 #endif
148 #ifdef CONFIG_X2TLB
149 	VMCOREINFO_CONFIG(X2TLB);
150 #endif
151 }
152 
153 void __init reserve_crashkernel(void)
154 {
155 	unsigned long long crash_size, crash_base;
156 	int ret;
157 
158 	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
159 			&crash_size, &crash_base);
160 	if (ret == 0 && crash_size > 0) {
161 		crashk_res.start = crash_base;
162 		crashk_res.end = crash_base + crash_size - 1;
163 	}
164 
165 	if (crashk_res.end == crashk_res.start)
166 		goto disable;
167 
168 	crash_size = PAGE_ALIGN(resource_size(&crashk_res));
169 	if (!crashk_res.start) {
170 		unsigned long max = memblock_end_of_DRAM() - memory_limit;
171 		crashk_res.start = memblock_phys_alloc_range(crash_size,
172 							     PAGE_SIZE, 0, max);
173 		if (!crashk_res.start) {
174 			pr_err("crashkernel allocation failed\n");
175 			goto disable;
176 		}
177 	} else {
178 		ret = memblock_reserve(crashk_res.start, crash_size);
179 		if (unlikely(ret < 0)) {
180 			pr_err("crashkernel reservation failed - "
181 			       "memory is in use\n");
182 			goto disable;
183 		}
184 	}
185 
186 	crashk_res.end = crashk_res.start + crash_size - 1;
187 
188 	/*
189 	 * Crash kernel trumps memory limit
190 	 */
191 	if ((memblock_end_of_DRAM() - memory_limit) <= crashk_res.end) {
192 		memory_limit = 0;
193 		pr_info("Disabled memory limit for crashkernel\n");
194 	}
195 
196 	pr_info("Reserving %ldMB of memory at 0x%08lx "
197 		"for crashkernel (System RAM: %ldMB)\n",
198 		(unsigned long)(crash_size >> 20),
199 		(unsigned long)(crashk_res.start),
200 		(unsigned long)(memblock_phys_mem_size() >> 20));
201 
202 	return;
203 
204 disable:
205 	crashk_res.start = crashk_res.end = 0;
206 }
207